4 ms·

I believe we are obliquely agreeing. To further my thoughts a bit, the distinction I would place on OS/2 over DOS is double: 1) first class memory protection

by kev009 2y ago

I believe we are obliquely agreeing. To further my thoughts a bit, the distinction I would place on OS/2 over DOS is double: 1) first class memory protection 2) full preemptive multitasking. The distinction I would place against all widely used modern desktop OSes is the lack of first class multi-user support. Early Windows gains cooperative multi-tasking like Mac OS classic but neither fundamentally use memory protection the way later OSes normalize and that turns out to be a pretty clear dead end. I believe there are extensions for both that retrofit protection in. Both also have some add on approaches to multi-user but are not first class designs. So, even the most robust single user system that implements full memory protection and preemptive multitasking still seems to be stuck in a valley. I.e. whatever the actual cost in terms of implementation and increase in cognitive workload for single user systems (i.e. "enter your administrative password" prompts on current macOS or Windows administrative accept dialogs) seems to be accepted by the masses. And note that this isn't an implicit a negative judgement, for instance I find BeOS or those in your list can be absolutely fascinating. And OS/2 is lovely even today for certain niche or retrocomputing things. Just pointing out that NT made a better bet for the long term, and some of that undoubtedly related to the difference of a couple years.. keep in mind OS/2 ran on a 286, which NT completely bypassed.

nullindividual 2y ago
Windows 2.0 for i386 was the first to introduce protected mode and preemptive multitasking. These features had to wait for Intel but it was available in 1987.
- kev009 2y ago
  In a limited sense, yes, Windows (without NT) increasingly /used/ memory protection hardware over its life but never in a holistic approach as we typically understand today to create a TCB. I don't believe Windows 2.0 implemented preemptive tasking, can you show a reference so I can learn?
  - deleted 2y ago
    [deleted]
  - jazzypants 2y ago
    I'm not that guy, but the Wikipedia article[1] is a decent jumping-off point, but I also found this blog article[2] talking about the different versions-- although it seems to get a couple things wrong according to discussion about it on lobste.rs[3] Finally, this long article from Another Boring Topic [4] includes several great sources. 1 - https://en.m.wikipedia.org/wiki/Windows_2.0#Release_versions https://en.m.wikipedia.org/wiki/Windows_2.0#Release_versions 2 - https://liam-on-linux.livejournal.com/78006.html https://liam-on-linux.livejournal.com/78006.html 3 - https://lobste.rs/s/4xfswa/what_was_difference_between_windows https://lobste.rs/s/4xfswa/what_was_difference_between_windo... 4 - https://anotherboringtopic.substack.com/p/the-rise-of-microsoft-windows-2x https://anotherboringtopic.substack.com/p/the-rise-of-micros...
    - lproven 2y ago
      That's my blog post -- thanks for the link. The Lobsters discussion was very interesting. Some people in there were extremely knowledgeable, but also very confrontational. Coming straight in going "that's all wrong!" is not a productive way to start a discussion IMHO. I didn't get any very firm conclusions from it. There are some very knowledgeable people out there on the WWW claiming, with convincing arguments, that Windows/286 couldn't run in 286 mode and only gave you 640kB ("conventional memory" in DOS terminology)+ 64kB HMA. Others, including from Microsoft, say no, Windows/286 did run in protect mode and could access 16MB of (segmented) RAM. I do not know for sure who is right.
  - fredoralive 2y ago
    AIUI Windows/386 2.x is basically a pre-emptive V86-mode DOS multitasker that happens to be running Windows as one of its tasks. So the GUI itself is cooperative, but between its VM and DOS VMs it can pre-empt. (Windows 3.x 386 mode is similar, with Windows 9x stuff in the Windows VM can pre-emptively multitask, mostly).
    - 2y ago
devbent 2y ago
Windows has had multi-user support for ages. That is how user switching in XP works, and how RDP works. You can have an arbitrary number of sessions of logged in users at once, only limited by the license for what version of Windows you have installed. There have also been versions of Windows that allow multiple users to interact with each other at once, but I believe these have all been cancelled and I do not know to what extent these simultaneous users had their own accounts.
- kev009 2y ago
  Well of course, Windows XP is a direct decedent of Windows NT. Maybe you are referring to Citrix or Terminal Server, which are also Windows NT technologies.
amaccuish 2y ago
Windows NT was multi-user from the start. The only change was the session object added in vista.

by kev009 2y ago

nullindividual 2y ago

Windows 2.0 for i386 was the first to introduce protected mode and preemptive multitasking. These features had to wait for Intel but it was available in 1987.

kev009 2y ago
In a limited sense, yes, Windows (without NT) increasingly /used/ memory protection hardware over its life but never in a holistic approach as we typically understand today to create a TCB. I don't believe Windows 2.0 implemented preemptive tasking, can you show a reference so I can learn?
- deleted 2y ago
  [deleted]
- jazzypants 2y ago
  I'm not that guy, but the Wikipedia article[1] is a decent jumping-off point, but I also found this blog article[2] talking about the different versions-- although it seems to get a couple things wrong according to discussion about it on lobste.rs[3] Finally, this long article from Another Boring Topic [4] includes several great sources. 1 - https://en.m.wikipedia.org/wiki/Windows_2.0#Release_versions https://en.m.wikipedia.org/wiki/Windows_2.0#Release_versions 2 - https://liam-on-linux.livejournal.com/78006.html https://liam-on-linux.livejournal.com/78006.html 3 - https://lobste.rs/s/4xfswa/what_was_difference_between_windows https://lobste.rs/s/4xfswa/what_was_difference_between_windo... 4 - https://anotherboringtopic.substack.com/p/the-rise-of-microsoft-windows-2x https://anotherboringtopic.substack.com/p/the-rise-of-micros...
  - lproven 2y ago
    That's my blog post -- thanks for the link. The Lobsters discussion was very interesting. Some people in there were extremely knowledgeable, but also very confrontational. Coming straight in going "that's all wrong!" is not a productive way to start a discussion IMHO. I didn't get any very firm conclusions from it. There are some very knowledgeable people out there on the WWW claiming, with convincing arguments, that Windows/286 couldn't run in 286 mode and only gave you 640kB ("conventional memory" in DOS terminology)+ 64kB HMA. Others, including from Microsoft, say no, Windows/286 did run in protect mode and could access 16MB of (segmented) RAM. I do not know for sure who is right.
- fredoralive 2y ago
  AIUI Windows/386 2.x is basically a pre-emptive V86-mode DOS multitasker that happens to be running Windows as one of its tasks. So the GUI itself is cooperative, but between its VM and DOS VMs it can pre-empt. (Windows 3.x 386 mode is similar, with Windows 9x stuff in the Windows VM can pre-emptively multitask, mostly).
  - 2y ago

devbent 2y ago

Windows has had multi-user support for ages. That is how user switching in XP works, and how RDP works. You can have an arbitrary number of sessions of logged in users at once, only limited by the license for what version of Windows you have installed. There have also been versions of Windows that allow multiple users to interact with each other at once, but I believe these have all been cancelled and I do not know to what extent these simultaneous users had their own accounts.

kev009 2y ago
Well of course, Windows XP is a direct decedent of Windows NT. Maybe you are referring to Citrix or Terminal Server, which are also Windows NT technologies.

amaccuish 2y ago

Windows NT was multi-user from the start. The only change was the session object added in vista.